Rocker arm



Dec. 11,-1951 J. R. WINTER, JR

ROCKER ARM 2 SHEETS-SHEET l Filed July 19, 1944 :Vm-rl Dec. M, 1951 J. R. WINTER, JR

ROCKER ARM 2 SHEETS- SHEET 2 Filed July '19, 1944 (wf i 552%@ INVENTOR.

Patented Dec. 11, 1951 UNITED STATES PATENT oFFlcE- ROCKER ARM John R. Winter, Jr., Detroit, Mich., assigner, by direct and mesne assignments, to John R. Win--V ter, Sr., Detroit, Mich.

Application July 19, 1944, Serial No. 545,597

s claims. (c1. 'J4-519) Y The invention relates generally to internal combustion engines and it has particular relation to a rocker arm adapted to be used for operating valves.

The ordinary rocker arm used in an internal combustion engine has bearing means at opposite ends and has an opening intermediate its end for mounting it on the engine block'for oscillatory movement. One end of the arm is moved by cam actuated means engaging the bearing means at that end, while the bearing means at the other end is engageable with the valve stem. Usually the latter bearing means is adjustable. While such rocker arms have been made by forging and other processes, the present invention isv particularly concerned with the provision ofa rocker arm made from stamped sheet metal and while it is not generally new to provide such a rocker arm, the present invention is concerned with improvements in both the arm andthe method by means of which it is manufactured.

One object of the invention is to provide an improved rocker arm made from sheet metal which is extremely strong and durable so that it may be used eiiiciently for a long period of time.

Another object of the invention is to provide such a rocker arm which may be made with accuracy, uniformity and precision, while still permitting its manufacture at a lower cost.

Another object of the invention is to provide an improved rocker arm comprising stamped sheet metal and a tubular bearing element extending therethrough, wherein the tubular element and stamping are connected together in an improved and very positive manner so as to permanently lock them in assembled relation.

Another object of the invention is to provide an improved method `of manufacturing a rocker arm such as last mentioned and more particularly an improved method for locking the tubular element to the stamping..

Another object of the invention is to provide a novel and eicientapparatus for assembling and locking the tubular element to the stamped arm.

Other objects of the invention will become apparent from-the following description, fromthe drawing to which it relates and from the claims hereinafter set forth.

For a better understanding of the invention reference may be had to the accompanying drawings wherein:

Figure 1 is a side elevational view of a rocker arm constructed according to one form of the invention;

Figure 2' is a plan view of the rocker arm shown 1byFigure1; v m v vFigure 3 is a cross-sectional view taken substantially along the line 4-4 of Figure 3;

Figure 5 is a cross-sectional view taken substantially along the line 5-5 of Figure 1;

Figure 6 is a cross-sectional view taken substantially along the line 6-6 of Figure 1; A

Figure 7 is a cross-sectional view of apparatus employed in forming a first head on the tubular hubl element adapted to extend through. the stamping; and f Figure 8 is a similar view illustrating the manner in which the tubular element is assembled with the stamping and the second head is formed. Referring to Figures 1, 2 and 3, the body of the arm comprises -a stamping I0 having laminations II and I2 integrally connected at one end by a substantially cylindrical portion I3, and initially, the laminations II and I2 arestamped from sheet metal to the desired shape and then are bent intermediate their ends to form the cylindrical portion. At the opposite end of the stamping, the laminations VII and I2 .haveoutwardly pressed portions I4 and I5, respectively. so as to form an opening I6 between them. After the metal is bent into the shape shown, the laminations may be welded at suitable points asindicated at I1, I6, I9, and 20.

At that end of the arm having the cylindrical portion I3, a bearing element 22 is mounted on the arm by means of a shank 23 having a pressed t in the opening in the cylindrical portion. The opening I6 at the other end of the arm has a threaded bearing element 25 threaded there,- through. A lock nut 26 adjustably holds the last bearing element in adjusted position. l

Intermediate its ends, the laminations II and I2 have aligned openings 28 and 29 and these may be formed in the metal prior to bending it into laminated form. A tubular element 30 extends through the openings 28 and 29 and is rigidly and positively connected to the Alaminations by means of outwardly bu1bed heads :il and 32 located at theouter sides of the laminations. These heads, as will be seen presently, are formed by.axially compressing the tubular element 30 and causing the heads 3| and 32 to draw up tightly against the laminations and thus when the heads are finally formed, theV laminations arestrongly and tightly drawn together and at the same time the tubular element is strongly and positively connected to the laminations. "7

Within the tubular element 30, a bearing sleeve -34 is provided and this may be made from suitable bearing material such as bronze, and preferably is split longitudinally at one point. The arm I proper is constructed from sheet steel and the tubular element may be cut from sheet steel trbing formed in any suitable manner.

In an arm of this type, lubricant is supplied through a hollow shaft, not shown, which extends through.the bearing sleeve 34. zThis hollow-shaft has oneor more. radial openings vthrough which the lubricant may ow and these openings are adapted to register during oscillatory movementv of the rocker arm with radial openings 36 and 31 formed in both the sleeve 34 and tubular-element 30. The openings 36.7and31 are located in alignment with the inner contactingfaces of the laminations Il and I2 and at this point, the rel spective laminations along the edges of the openings 28 and 29 are beveled as'indicatedat394 and 40 for a part of the Way around the openingsoas,

to provide a lubricant space 4| between the beveled .,faces. l.This .circumferentially extending lubricantspace.- extends slightly. beyond .the openings ..36 y.and ..31 and hence lubricant fjlowing through ,either opening .will-now circumferentially.,through .the space. Substantiallymidway between theopenings v36 .and 31,.,a verticallyexlAttentionis .directed to,several structural characteristics. as. may. beseen in Eigurej 3, Vparticularly. Itwill. be observedthat ,the heads 3 Iv and 32 have substantiallyfull v surfaceengagement .withjthelaminations Il and I2 and therefore the inner face Lofeach of ftheheads'3l and 32 is brought. substantially into a radial position. It Vwill also.be 'observed that each head actually embeds itself slightly, as. indicatedy at '4B, in the .laminationaround theinner edge of theopening.

It rwill. also be notedthat' the outer peripheral .-,surfaceof each of the annularLheads 3i and32 ',.Is-substantially axiaLas indicated at 49 and that lthe axially vouterface of` each headlis slightly inclined tothe radial as indicated at50. Also,{it .willbe observedinconnection with'Figures 3 and `4 that the element 3011s pressed.slightlyoutwardly into.. the, lubricant space- 4I as indicatedat 52 Itherebylforming a circumferential keyorlock between' ithe tubular. element and stamping.

.,'Nowreferring .to Figure '1, ,the tubular felement .30 is first placed vonanarbori andthen issub- ;Iectedto..axiallycompressive Lforces by. means vof ,tubulandies I and 62 .slidable,onthearbor. The diellmasran annularfrecess formed by a radial shoulder-.64, andaperipheral walli65 for confining a predetermined end pcrtion of the tubular ele- .ment-3ll.and similarlythe dieIZ `has anannular spaceformed .bya radial shoulder G6, and .a peripheralwal1-:61 for conning a major ,portion of the .remainderofy thev tubulareelement. At the .inner-ends-of ,theperipheralzsurfaces 6 5 and 61, the diefelement ,-61 hasan outwardly .directed andslightly tapered face 68, the eradial dimension ,of 4:which will :correspond to fthe :height` fof the head to :be `formed. during .f axiaL compressionacf 4 the tubular element. At the inner end of the peripheral surface 61 on the die element 52, a similar end surface 69 is provided, but this surface is radial in direction. The die 62 has an outer portion 10 projecting axially beyond the end surface 69 and this portion telescopes over a yportion 1| on the diefII. .The two die elements are limited in theirv movements towards each other by contact as indicated at 12.

The tubular element 30 initially is placed on the arbor 60 and then the two die elements are Ymoved thereover and as the shoulders 6'4 and 66 press theends ofthe tubular element, that portion of the, element between the approaching surfaces 68 Aandfil bulbs outwardly. The arbor connes the inner periphery of the element'l in a precisemannersothat the inner diameter of the ,elementi is maintained uniform and of the desired dimensions. As the dies continue moving to- .wards ,each other, ,.the", .annular head 3 I is y.pre-

.vented fromfexpanding `o utwardlybeyond a cer- .,tainamount by the inner surface of the portion "10 on die element 62 and hence as the surfaces =.6 8 and 69. move towards their nal positions, the

metal .inthe, head isl thereby confined more and I. more. Finally, thehead is'formed with the radial surface onone side and the slightly inclined surface at its other, with the outer peripheral surface ofthe headsubstan'tially axial. The taperedl surface 68 isparticularly desirable, in that as it moves against the b ulbing head, it presses .the V.radially outer part of the head' strongly vagainstthe radially youter part of the face 69 so asthereby to insure alfull radial surface on .the head. Hence thehead has a fully radial surface on itsinnerside anden its outer side it is reinforced by a tapered' formation.

`After the single Y head is jthusfformed on the element. 30,the ldiesarey removed and the element is insertedjthrou'ghtheopenings28 and29 ,formed in the laminations Il .and' I2. The same arbor 60 may be usedpbutinV the final assembly 32. isnotas yet formed, the die element is as yet substantially spaced from the lamination I2. As

the Vdie elements 15 and.16 are moved towards eachother, outwardbulbing of the head 32 oc curs and it is nallyishaped in .the samemanner v.as .the head 3l when V4the ends ofboth dies directlycontact the arm. ADuring thisaxialcorn- ,pression of the element .the outwardly ldirected ribor key 52 ispressed outwardly into thelubrivcant space 4I andfat the same time slight embedding of the heads 3| and v32inthe laminations occurs as indicated previouslyat 4 8.

.While according .tothe foregoing description :the 4 tv vo heads. 3l and 3 2 .areformedinz sequential operations, they, could also beformed .simultaneously. This could be eiected byplacingthe tubular'element onthe arbor 6 0, theninserting the arbor andelement through the lopenings in the laminated arm, and then movingthe dieA ele- ,Aments 15 and 16 simultaneouslyyto' form the heads.

It should be understood that substantially4 full radial surface Contact ispbtained between v the heads 3 I; and 32 and thezlespectiye laminations Y tubular elementy is lexpanded within the openings 28 and 29 and hence is tightly connected thereto by-a strong, forceful contact'resulting from. `expansion of the metal Vforcefully in a hole-filling manner. The dies now may be removed along with the arbor. y

It isv desired to point out several advantages of the invention. In the first place, by `manufacturing the rocker arm from a stamping and a separate metal tube, drawing of the sheet metal is avoided and therefore the Vstamping can be made from a higher carbon steel, which results in greater stiifness'and strength. Furthermore, no rehardening is necessary such as would be required if the stamped stock had been drawn. Again, by using the pin 22, and press tting it into place, welding thereof is eliminated and the pin therefore may initially be heat treated to obtain the desired hardness. It is of course evident that the pin may be driven out and replaced so as to permit replacement of worn pins. In this connection, the integral cylindrical portion is important since it enables obtaining a greater amount of contact with the pin so as thereby to hold the pin securely in place by a press fit while still permitting replacement of the pin when worn.

Furthermore, since no drawing operation is involved, the stamped metal will be of uniform thickness and no trimming or reshaping is required. By using simple spot welding at the points indicated, the laminations may be connected by welding in a simple and inexpensive manner although it shouldbe understood that the mechanical lock between the tubular element and the laminations is extremely strong and positive. It follows that the weld and mechanical lock providel great strength in the assembly.

With respectl to the tubular element, this can be made easily out of tubing or drawn from flat sheets, and hence it is accurate and the least amount of machining is required. Furthermore, it can easily be varied in length so as to provide the desired hub length on the rocker arm. Regardless of length, the tubular element is anchored in proper relation to the arm and in particular the direct contact between the inner ends of the dies and the opposite sides of the arm insures that the axis of the tubular element will be accurately aligned with the axis of the opening in the arm. In other words, the arbor and dies maintain the cylindrical shape and dimensions of the tubular element with accuracy and the final contact; between the dies and arm insures alignment of the element and opening in the arm. Hence, the axis of oscillation of the arm can be located uniformly.

Furthermore, in regard to the tubular element, the upsetting operations are active throughout the length thereof, and where the tube is confined by the arbor and dies, the surfaces of the tube are smoothed out and variations due to mill and production operations are corrected. By selecting a proper and predetermined length of tubing, the upsetting can be such as to correct variations las indicated, and furthermore the inside diameter can be made uniform and highly accurate as the metal is upset along the arbor. In other Words, the straight portions of the tubular element can be sufciently upset against the arbor as to result in a very smooth inside surface which is accurate and uniform in diameter. Moreover, these operations result in the axis of the tubular elementbeing disposed properly with respect to the stamping. I-Ience the bearing bushings properly fit the `tubular element, thereby eliminating considerable `ous modifications may be made without departing from the scope of the appended claims.

What is claimed is:

. 1. A rocker arm assembly comprising an arm having a transverse opening, a tubular hub element extending through the opening, and means rigidly connecting the arm to the hub element and comprising annular heads on the element and tightly engaging and bearing inwardly against respectively opposite sides of the arm and being at least slightly embedded therein in an area surrounding said opening, and oil channel-dening means comprising an opening extending through the arm and a communicating opening extendingthrough the hub in an area between said bulbed heads.

2. A rocker arm assembly comprising an arm having a transverse opening, a tubular hub element extending through the opening, means rigidly connecting the arm to the hub element and comprising an annular, bulbed head on the element and tightly engaging and bearing against one side of the arm and being at least slightly embedded therein in an annular area surrounding said opening, and oil channel-defining means comprising an opening extending through the arm and a communicating opening through the hub in an area surrounded'by the arm.

3. A rocker arm assembly comprising an-arm having a transverse circular opening, a circumferentially extending portion of the Wall defining said opening being of increased radial dimensions intermediate the axial ends of the wall so as to provide a recess, a tubular hub element extending through the opening, and means rigidly connecting the element to the arm and including metal extended outwardly from the element into the recess.

4. A rocker arm assembly comprising an arm having a transverse opening, the wall defining said opening being generally cylindrical and along a circumferentially extending portion thereof having an increased radius between axial ends of the wall so as to define a circumferentially extending groove or recess in said wall; a tubular hub element extending through the opening, and means rigidly connecting the arm and tubular element including metal extending outwardly from the element and into the groove.

5. A rocker arm assembly comprising a plurality of laminations forming the body of the arm ,and having aligned transverse openings, a tubular hub element extending through the openings and having a tight hole-filling engagement with the edges defining the openings, annular, bulbed heads on the hub element at opposite sides of the body respectively and tightly engaging and bearing inwardly against the sides of the laminations f so as to be at least slightly embedded in the laminations to hold them strongly and tightly drawn together, and oil channel dening means comprising an opening extending between the laminations and a communicating openingthrough the hub wall.

6. A rocker arm assembly comprising a plurality of laminations forming the body of the arm and having aligned transverse openings, a tubular hub element extending through the openings, annular, bulbed heads on the hub element at oppofemmes@ the laminationsfso as' tobeat least slightly-lieux- 'bedded in the laminations to hold them strongly 'and tightly drawn together, and oil channel devfning means comprising communicating openings :extending through the hub Wall and through the body of the arm to coact in conducting lubricant from the hub to an end of the arm.

JOHN R. WINTER, JR.

REFERENCES CITED The following references are of record` inthe le `of this patent:

-UNITED STATES PATENTS Number Number Name Date uKonigslow n Mar.\27,1923 'Skillman Feb. 24, 1931 vrSkillmem May 16, 1933 Skillman Jan. 16, 1934 Leake Oct. 17, 1939 Leake Apr. 4, 1944 FOREIGN PATENTS Country Date Great Britain July 31, 1930 

